The present invention relates to a method of automatically removing any contamination of a large number of guide rollers disposed on a paper discharge side with respect to a printing portion of a rotary press, and more particularly, the present invention affords a washing method for guide rollers which applies a washing liquid to printing paper, brings the printing paper into sliding contact and provides a difference in their relative speed to wipe off contamination.
Further, the present invention relates to an apparatus for automatically removing any contamination of the guide rollers, and more particularly, the present invention affords a guide roller washing apparatus which utilizes printing paper as such, applies a washing liquid to the printing paper, brings the paper into contact with the guide rollers, provides a difference of relative speed between the paper and the guide rollers, and wipes off contamination.
Rotary presses for newspaper generally employ a construction in which three to four printing units are juxtaposed with one another. FIG. 2 of the accompanying drawings illustrates partially one example. Only two printing units are shown in the drawing for simplifying the illustration. Each printing unit 10 is equipped with a printing portion 16 consisting of a blanket cylinder 12 and the like, and a paper feed portion 20 which supports wound newsprint paper 18. Travelling paper 22 pulled out from the paper feed portion 20 reaches the printing portion 16 while being guided by a plurality of guide rollers 24, where it is printed, and is further guided by a plurality of guide rollers 26 to a folding machine (not shown), where the printed paper is cut and folded.
Generally, from 15 to 20 guide rollers 26 are disposed on the paper discharge side of the printing portion 16, or in other words, between the printing portion 16 and the folding machine. Since these guide rollers 26, particularly four to six guide rollers near the printing portion 16, come into contact with the travelling paper immediately after printing, large quantities of printing ink and paper dust attach to them. The guide rollers 26 are chromium-plated in a smooth condition, but the printing ink and paper dust are unavoidably attached thereto. Thus, they are contaminated unavoidably in the course of printing of large quantities of paper.
When the guide rollers 26 are contaminated, the paper surface gets dirty and since the attached and solidified foreign matters generate corrugation on the paper surface, longitudinal creases are likely to occur on the travelling paper and the quality of the printed matter drops seriously.
Therefore, the contamination of the guide rollers must be cleaned and wiped off at the time of replacement of printing plates or at the finish of printing. Cleaning devices have already been developed to automatically wash and clean a blanket drum, but suitable washing devices have not yet been developed for a large number of guide rollers. For this reason, they must be washed and cleaned manually at present.
In the case of a rotary press of newspaper having three to four printing units, the printing work is carried out generally by four to six workers. In this case, from about 15 to 20 minutes are necessary for three to four workers to wash the guide rollers so that the loss in time and economy is extremely great. Since the workers must enter the complicated inside of the rotary press to which the printing ink attaches, the body and clothes get dirty and the washing work is not pleasant. Moreover, the washing work is dangerous because it must be carried out sometimes at a high place.